The present invention relates to an evaporation burner capable of readily attaining a complete combustion of a preheat burning flame, by preheating rapidly to the vaporized gas generating ambient temperature a gas generating unit and a burning unit arranged adjacent to each other, thereafter vaperizing or gasifying the fuel supplied together with the combustion air, and burning the gas mixture through a number of injection flame ports.
The present applicant has proposed an evaporation burner in the Japanese Patent Publication No. 21170/83, in which a gas generating unit through which a preheat burning flame flows and a burning unit having therein a hollow gas chamber and a number of flame injection ports in its surface are arranged adjacent to each other. A distal or free end of the gas generating unit is connected to the burning unit through communication windows, so that the gas generating unit and the burning unit are rapidly preheated from the inside by the flow action of the preheat burning flame generated in the gas generating unit, and at the same time, a part of the preheat burning flame injecting through the injection ports is directed to the gas generating unit to heat the gas generating unit from the outside. Thereafter the fuel supplied into the gas generating chamber is vaporized or gasified togehter with the combustion air to generate a gas mixture. Then, the gas mixture is directed upwardly from the injection ports of the burning unit while heating the gas generating unit around its periphery, thereby burning the gas mixture. Thus, the evaporation combustion is continued.
In such a conventional evaporation burner, since the burning unit connected to the distal and side of the gas generating unit is closed except for the injection ports, the preheat burning flame introduced from the gas generating unit to the burning unit is gradually stagnant in the burning unit. Therefore, there will be a phenomenon where the burning flame flows reversely to the gas generating unit. As a result, an incomplete combustion is caused due to the fact that the area of the combustion chamber for the preheat burning flame is smaller. The material generated resulting from the incomplete combustion will plug or clog the injection ports, thereby resulting in degradation of the preheat effect of the gas generating unit. In addition, the material is also adhered to the inner surfaces of the gas generating unit and the burning unit, resulting in degradation of the vaporized gas generating performance. It is therefore difficult to continue the constant amount vaporized combustion in a stable manner.